Field of the Invention
The present invention pertains to a fuel delivery assembly for delivering fuel in a controlled manner to equipment, including, but not limited to, hydraulic fracturing pumps and related equipment in the oil and gas industry. More particularly, the present invention pertains to a fuel delivery assembly for providing a gravity-fed fuel supply to hydraulic fracturing equipment in the oil and gas industry.
Brief Description of the Prior Art
Geological formations may contain deposits of oil and/or natural gas. However, in many cases such geologic formations have low permeability; due to such low permeability, hydrocarbon deposits may not flow from said geological formations at a desired flow rate. As a result, hydraulic fracturing (“fracking”) is frequently employed to artificially produce fractures in such geological formations to stimulate the flow of natural gas or oil to wellbores penetrating the formations, thereby increasing the volumes of hydrocarbons that can be recovered.
Generally, the fracking process occurs after a well has been drilled to a desired depth and a steel casing has been installed into a wellbore. Such casing is perforated within a target formation (typically, but not always, a low permeability shale formation) that contains oil or gas. Fracturing fluid is injected into a well at high pressure and flows through the perforations and into the surrounding formation; in many case, the fracturing fluid typically comprises water, proppant, and a number of chemical additives that open and enlarge fractures within the rock formation.
Fracturing fluid is pumped into a wellbore at a rate that is sufficient to increase pressure at the target depth (which is generally determined by the location of the well casing perforations), and eventually, the target formation will not be able to absorb the fluid as quickly as it is being injected. At this point, the pressure created exceeds that of the fracture gradient (pressure gradient) of the rock and causes the formation to crack or fracture. Once the fractures have been created, injection ceases and the fracturing fluids begin to flow back to the surface. Materials that are generally called proppants (i.e., sand, ceramic pellets, or any other small incompressible particles), which were injected as part of the fracturing fluid mixture, remain in the target formation to hold open the newly created fractures.
Hydraulic fracturing equipment used during fracturing operations typically comprises a slurry blender, at least one high-pressure, high-volume fracturing pump, and a monitoring unit. Additionally, a variety of associated equipment is typically used in fracking operations, including, but not limited to, at least one storage unit and a plurality of hoses and gauges that can operate over a range of pressures and injection rates. Much of this equipment is powered by gas or diesel powered engines.
In many cases, fuel is manually delivered to each of these engines. In other cases, fuel systems utilize one or more fuel pumps to deliver fuel to multiple equipment fuel tanks. Such conventional fuel systems typically comprise sensors, networks, touch screens, powered valves, switches, regulators, or other similar devices, in order to keep fuel tanks relatively full of fuel. Such conventional systems can be very complex and have a large number of potential failure points; in some cases, such fueling system include electronic sensors to electronically monitor fuel levels in each tank and remotely open and close valves in order to control fuel flow.
Fuel pump systems that employ electronic sensors typically require individual fuel lines from a main fueling unit to each individual fuel pump, and from each individual fuel pump to an equipment fuel tank, thereby resulting in significantly more hoses or conduits disposed across a location. Such additional hoses typically results in more potential failure points, more cost, and more labor expense.
With manual refueling systems, personnel must remember to regularly refuel all equipment fuel tanks on location. Should such personnel neglect or fail to refill any tank, one or more pumps or other critical pieces of equipment (such as, for example, a sand belt or blender) may run out of fuel. This can result in cutting stages of a fracking operation short or even causing severe damage to a well.
Thus, there is a need for a fuel delivery system that is safer, more reliable and less expensive to operate and maintain than conventional refueling systems.